Linux File Hierarchy System

Introduction of FHS

File System Hierarchy Standard is a standard set of directories for linux system.it includes file and subdirectories contents and gives linux software developers ability to locate file on any linux system.

/root (Boot File)

It is the root,user`s home directory.it includes boot loader related files.

/bin (Binary Commands)

Contain binary executables.the common linux commands you need to use in single user mode are located under this directory.the commands used by all theusers of the system are located her.for example : ps,ping,grep,cp.

/sbin (System Binaries)

To contain system library commands.(Used by administrator). just like /bin,/sbin also contains binary executables.the linux command located under this directory are used typically by system admin,for system maintenance purpose for example: iptable,reboot,fdisk.

/etc (Configuration File)

To contain system specific configuration tools.it includes configuration file required by all programs.this also contains start up and shut down shell script used to start/stop individual programs.

/dev (Device File)

To contain device files like hardware drivers,printers etc.it also includes terminal device,USB or any device attached to the system.

/proc (Process Information)

To contain process and kernel information.this is pseudeo file system,which contains information about running process.for example: /proc/{pid} directory contain information about the process with that particular pid.this is a virtual file system with text information about system recourses.

/var (Variable Files)

To contain log files & spools. the contain of the files that are expected to grow can be found under this directory.this includes system log files(/var/log),packages abd database files(/var/lib),emails (/var/mails), print queuses (/var/spool), temporary files needed across reboots (var/tmp).

/tmp (Temporary Files)

To hold temporary files created by programs and users. file under this directory are deleted when system is rebooted.

/usr (User Programs)

To contain most system commands and utilities - contains the following directory.

/usr/bin - User Binary Commands

/usr/games - Educational Programs & Games

/usr/include - C Programming Header File

/usr/lib - Libraries for /usr/bin and /usr/sbin

/usr/local - Local Programs

/usr/sbin - System Binary Commands

/usr/share - File that are Architecture Independent

/usr/src - Source Code

/usr/X11R6 - The X Windows System

/usr/local/apache2

/home (Home Directory)

It is the default location for user`s home directory.(Home directory for all users to store personal file.)

/boot (Boot Loader)

To contain linux kernel and files used by boot loader.

/lib (System Libraries)

it contain shared program library(used by the commands in /bin and /sbin)as well as kernel modules.)

/opt (Optional addon Application)

To stor additional software program.it contain add on application from individual vendors(add on application should be installed under either /opt or /opt/ subdirectory.

/mnt (Mount Directory)

It is empty directory used by accessing(moubting)disks,such as floppy disk,CD-ROM.(Temporary mount directory where sysadmins can mount file system)